Bird Atlas

The San Diego County Bird Atlas is one of the most ambitious research projects the San Diego Natural History Museum has ever undertaken. It establishes a new benchmark for knowledge of birds in the region of the United States with more species than any other: 492 natives, migrants, and well-established exotics. Just from 1980 to 2000 the county's human population increased by over 51%, and the status of many of the county's bird species has been changing at an equally rapid rate. Twenty percent of the county's surface burned in 2002 and 2003, making the atlas a basis for assessing the effects of these firestorms without precedent in recorded history. The atlas can serve as the basis for evaluating the effectiveness of the Multiple Species Conservation Plan and similar land-management programs underway throughout the county. It reaches a level of detail unmatched in previous publications, a level far more relevant to conservation planning. With this atlas, the birds of San Diego County are now among the best known in the world.

The complete San Diego County Bird Atlas is now available through Google™ Earth. This interactive application, designed by John Sanborn, enables you to generate a list of birds recorded in each atlas square, as well as to read the text and to see the distributions overlaid over satellite images of San Diego County, as you design them. Publication of the atlas as a website was made possible by grants from the San Diego Foundation, in part under its Environment Program, in part by through its Blasker-Rose-Miah Fund for science and technology, and in part through the recommendations of anonymous individual donors.

The San Diego County Bird Atlas is based on the work of over 400 volunteer observers who spent over 55,000 hours in the field from February 1997 to February 2002. The observers recorded their results in a framework of 479 grid squares across the county, generating databases of nearly 400,000 records. The atlas' text reflects discoveries through spring 2004.

The San Diego County Bird Atlas addresses all the county's birds—wintering birds, migrants, and exotics, as well as breeding birds. There is at least one map for every regular breeding and wintering species and a chart showing the seasonal distribution of the nesting activity of each nesting species. Each species account covers breeding distribution, nesting habits and schedule, migration, winter distribution, conservation outlook, and taxonomy, if relevant. Observations are put in the context of each species' biology and history, to identify trends in ranges and numbers, and to search for the factors responsible for these trends.

The atlas is illustrated with 468 photographs showing 89% of the species covered. Most of the photographs were taken locally and show the species in plumages typically seen in San Diego County. The primary photographer contributing his talents to the atlas is the nationally renowned Tony Mercieca of Chula Vista; other contributing photographers include Ken Fink of San Diego, Jack Daynes of Poway, Brian Sullivan of San Diego, Ken Kurland of the Imperial Valley, and Richard Webster of Portal, Arizona.

The San Diego County Bird Atlas generated many new discoveries: 11 species nesting in the county for the first time, wintering of the Gray Vireo in the elephant trees of the Anza-Borrego Desert (first discovery of this species wintering in California), spread of species into areas where they were previously unknown, data from some areas that were biologically unknown before the atlas study, information on sites critical to rare, patchy, and colonial species, information on which species are adapting to urbanization and which are retreating from it, and information on how birds respond to the cycle of rain and drought.

The San Diego County Bird Atlas is an accomplishment of the entire community: sponsors are the California Department of Fish and Game, California Department of Transportation, California State Parks, National Fish and Wildlife Foundation, Palomar Audubon Society, San Diego Audubon Society, San Diego County Water Authority, San Diego Unified Port District, Sweetwater Authority, U.S. Forest Service, U.S. Navy, Zoological Society of San Diego, and 160 individuals, societies, and companies.

From 1997 to 2002 the San Diego Natural History Museum published the newsletter Wrenderings for volunteers and supporters of the bird atlas as the field work was underway. These newsletters chronicle the project from start to finish with contributions from many participants and can be viewed on this website . Each issue of Wrenderings featured an article on one or more bird-identification problems .

The atlas' author is Philip Unitt , Curator for the San Diego Natural History Museum's Department of Bird and Mammals, editor of the journal Western Birds , author or co-author of over 30 scientific papers and reports, and co-author of Birds of the Salton Sea: Status, Biogeography and Ecology , published in 2003 by University of California Press.

This atlas will be useful to the policy makers who are making irrevocable decisions about our future, birders at all levels, and the people of San Diego County, who need to understand their natural heritage if that heritage is to have any future.